When humans suffer an injury to one eye, are born with one eye, or have partial function in one eye, their depth perception will be impaired or absent. This happens because complete depth perception is achieved through binocular visual input. With the use of one eye, a human is only capable of gathering monocular input. In many cases, such as where one eye is capable of some level of functional vision and the other eye is capable of partial vision, where use of one eye has been lost subsequent to development of depth perception, or where only a single eye is capable of vision, it is desirable that depth perception be facilitated, emulated or regained, or that some benefits of depth perception be presented in a manner perceptible to a person without biological depth perception.